I had a very large pre cancerous colon polyp, discovered during a colonoscopy. It was too big for the doctor to remove. He said that resection surgery used to be necessary but now, in many cases, has been replaced by EMR (endoscopic mucosal resection)--a non-invasive procedure which, from a patient perspective, seems much like a colonoscopy. Fortunately, my provider--UCSF--has a doctor who specializes in EMR--not every facility does it. It was performed on an outpatient basis and the large polyp is gone with no side effects. It may not be appropriate for all cases, but it's worth exploring and asking about.